Colorado Livestock Disease Recap

LAKEWOOD, Colo. – The Colorado Department of Agriculture and Colorado producers have had a busy summer protecting livestock from diseases that affected this state’s largest agricultural sector – animal industry.

“The collaboration between livestock producers, private practice veterinarians, our veterinary diagnostic laboratories and our Department were important in reducing the risks and mitigating the effects of livestock disease in our state,” said CDA’s State Veterinarian, Dr. Keith Roehr.  “In the EHV-1, EHD and anthrax disease investigations, the timely and effective laboratory diagnostics at the Colorado State University’s Veterinary Diagnostic Laboratory were vitally important.”

Overall update for 2012 to date:

ANTHRAX
This investigation began in August, 2012. In all, approximately 55 cattle died due to an anthrax outbreak; four Logan County premises were quarantined and subsequently released after fulfilling disease control requirements.  Anthrax can develop naturally in soil; the spores can become active in association with periods of marked climatic or ecologic change such as heavy rainfall, flooding or drought which can then expose the anthrax spores to grazing livestock. In these areas the spores apparently revert to the vegetative form and multiply to infectious levels so that cattle, horses, mules, sheep and goats may readily become infected when grazing such areas.

BOVINE TRICHOMONIASIS
The Department sends monthly updates on “trich” in the state.  As of 10/25/2012, there are currently two positive trich locations in two Colorado counties:  Las Animas and Pueblo. So far this year, there have been 12 trich cases in eight counties: Conejos, Kit Carson, La Plata, Las Animas, Montezuma, Pueblo, Weld and Yuma.  Monitoring and testing herds is a vital step in preventing this disease; in 2008, 43 locations tested positive for trich compared to 13 locations in 2011. Trich is a costly, yet preventable, infection that can affect dairy and beef cattle.  If bulls become infected, the percentage of open cows in a herd can increase from 5 to 30 percent.  It is always important for producers to consult with their herd veterinarian on best management practices for disease control.

EPIZOOTIC HEMORRHAGIC DISEASE (EHD)
Yak and cattle at seven locations in Colorado tested positive for (EHD) which is a viral disease that affects deer, cattle and, most recently, yak.  Signs of EHD include fever, loss of appetite, weakness, respiratory distress, and swelling of the tongue, and erosive lesions in the mouth.  The disease cannot be transmitted by direct contact and is spread by insects, most commonly midges or gnats.

EQUINE HERPES VIRUS (EHV-1)
In early May, one Colorado horse tested positive for EHV-1.  Prior to exhibiting signs of disease the affected horse had recently traveled to Colorado from Iowa.  This Douglas County horse was euthanized after showing severe neurological signs associated with the disease.  After the initial case was diagnosed, several exposed horses were monitored closely and fortunately there was no further spread of disease.  Good preventative disease measures instituted by the horse owners helped to control any possible disease spread.  EHV-1 is not transmissible to people; it can be a serious disease of horses that can cause respiratory, neurologic disease and death.  The most common way for EHV-1 to spread is by direct horse-to-horse contact.  The virus can also spread through the air, contaminated tack and equipment, clothing and hands.

VESICULAR STOMATITIS (VS)
Two quarantines were issued in August after two horses in Las Animas and Conejos County tested positive for VS; the quarantines have now been lifted.  The State Veterinarian’s Office continues its travel requirement for horses, mules, cattle, bison, sheep, goats, swine, and camelids entering the state from states with confirmed cases of VS.  This requirement states that health certificates should include the following statement from the issuing veterinarian, “I have examined the animal(s) represented on this Certificate of Veterinary Inspection (CVI) and have found no signs of vesicular stomatitis and they have not originated from a premises under quarantine for vesicular stomatitis.”

WEST NILE VIRUS
The number of equine cases of WNV increased in 2012.  The 14 cases were spread throughout a wide area of Colorado as there were horses diagnosed in Delta, Fremont County, La Plata, Larimer, Mesa, Montrose, Pueblo and Weld County.  Horse owners should consider vaccination and insect control as effective tools to prevent disease.

“Livestock move throughout the state and across the country on a daily basis making investigating and monitoring livestock diseases an enormous task but the State Veterinarian’s Office is committed to doing our best to protect the health of the animals and the economy of the livestock industry,” said Dr. Roehr.

For more on CDA’s State Veterinarian’s Office, visit www.colorado.gov/ag/animals.